The Effects of Interrupting Prolonged Sitting With Bouts of Physical Activity on Neurocognitive Function in Obesity (SITLess)

SIT Less! Interrupting Prolonged Sitting With Brief Physical Activity Bouts to Improve Neurocognitive Function in Adults With Obesity

It is projected that by 2030 almost 50% of adults in the USA will have obesity. High sedentariness and physical inactivity contribute to the obesity pandemic. Neurocognitive deficits compound the global burden of obesity. Specifically, adults with obesity underperform on tasks of executive functioning, which underpin goal-directed behavior and have been linked to occupational success. Growing evidence suggests poorer executive functioning among more sedentary adults. Emergent studies have shown that accumulating sedentary time in prolonged bouts (e.g., remaining sedentary continuously 20 min or more) may decrease the ability to control distractions along with working memory. Interrupting prolonged sitting with brief bouts of physical activity is an effective strategy to improve postprandial glucose metabolism. However, the effects of this simple intervention on neural processes supporting executive functioning remain unknown. Accordingly, the aim of this study is to test the effects of interrupting prolonged sitting with frequent (every 30 min) but brief (3 min) physical activity bouts on inhibitory control, working memory, and their neuroelectric indices (N2, P3a, and P3b components of event-related brain potentials). Our secondary aim is to explore the potential mechanisms underlying the effects of interrupting prolonged sitting with physical activity on cognitive and brain function through glucose metabolism and insulin physiology. Findings from this study will help advance our understanding of how restructuring sedentary time may help improve cognitive and brain functions among adults with obesity.

Study Overview

• Status: Active, not recruiting
• Conditions: Obesity
• Intervention / Treatment: Behavioral: Physical Activity Breaks Intervention; Behavioral: Talking Breaks Control

Detailed Description

Measurements of cognitive and brain function will be taken before, and after three hours of prolonged sitting. Metabolic, heart rate, and blood pressure measures, along with the ratings of fatigue will be collected before and during the three-hour prolonged sitting time. The prolonged sitting time will be either interrupted with physical activity breaks or with sedentary breaks (attention control). Habitual physical activity, sedentary behavior, sleep, and dietary intake will also be assessed.

• Study Type: Interventional
• Enrollment (Actual): 45
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Illinois
    • Urbana, Illinois, United States, 61801
      • University of Illinois at Urbana-Champaign

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 21 years to 55 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• • Informed consent

  • Age 21-64 years
  • BMI within ≥ 30 and < 40 kg/m2 range
  • Pre-menopausal
  • Fasting plasma glucose (FPG) < 100 mg/dL
  • Resting blood pressure: systolic < 160 mmHg or diastolic < 100 mmHg
  • Employed in sedentary occupation (i.e., participants reporting sitting on average 6 h/d on a weekday and with objectively assessed sitting time ≥ 8 h/day)
  • Physically inactive (i.e., engaging in < 150 min of moderate or < 75 min of vigorous or any combination of the two intensities per week)
  • Participants must have had no prior diagnosis of cognitive or physical disability (e.g., ADHD, severe asthma, epilepsy, chronic kidney disease, or dependence upon a wheelchair/walking aid)
  • Free of medication that could affect cognitive function or metabolism
  • Normal or corrected-to-normal vision based on the minimal 20/20 standard in order to complete the cognitive task (below 20/20 vision)
  • Must be able to engage in vigorous exercise
  • Fluency in English

Exclusion Criteria:

• • Impaired glucose tolerance defined as fasting plasma glucose (FPG) < 100 mg/dL

  • Oral glucose tolerance test (OGTT) blood glucose values ≥ 200 mg/dL
  • Participants with any psychiatric, neurological or metabolic disorder
  • Participants who have or are currently taking the medication that could affect cognitive function, metabolism or weight status
  • Participants with substance abuse
  • Participants with a standardized score on the test of general cognitive abilities below 85
  • Participants with anemia
  • Pregnant women or those with a possible pregnancy
  • History of injury to the spinal cord

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Physical Activity Breaks Intervention; Participants will sit continuously for 3 hours and interrupt their sitting by walking on a treadmill at a moderate intensity for 3 min.	Behavioral: Physical Activity Breaks Intervention; Participants will be asked to walk on a treadmill for 3 min at a moderate intensity (55% of heart rate reserve) at an increasing speed and incline to reach and maintain their target heart rate.
Active Comparator: Talking Breaks Control; Participants will sit continuously for 3 hours. They will interrupt solitary sitting activities (while remaining seated) by talking to a researcher for 3 min on pre-selected topics of general interest.	Behavioral: Talking Breaks Control; Every 30 min a researcher will start a brief conversation with a participant based on a pre-selected topic, which will change with each break. Topics are standardized across participants and include, for example, pollution, smart clothes, and hydration. A presentation will be followed by questions and answers. The break will last 3 min.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Neuroelectric measures of inhibitory control - P3 component of event-related potentials (ERPs)	The change in the P3 component measured during the modified flanker task	Assessed immediately before and after the intervention (on the same day as intervention)
Neuroelectric measures of inhibitory control - N2 component of event-related potentials (ERPs)	The change in the N2-ERP component measured during the modified flanker task.	Assessed immediately before and after the intervention (on the same day as intervention)
Inhibitory control measured with a modified flanker task - accuracy	The change in accuracy on the modified flanker task	Assessed immediately before and after the intervention (on the same day as intervention)
Inhibitory control measured with a modified flanker task - reaction time	The change in measures of reaction time on the modified flanker task	Assessed immediately before and after the intervention (on the same day as intervention)
Neuroelectric measures of working memory - P3-ERP component	The change in the P3-ERP component during the n-back task.	Assessed immediately before and after the intervention (on the same day as intervention)
Working memory measured with an n-back task - accuracy	The change in accuracy on the n-back task	Assessed immediately before and after the intervention (on the same day as intervention)
Working memory measured with an n-back task - reaction time	The change in measures of reaction time on the n-back task	Assessed immediately before and after the intervention (on the same day as intervention)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Post-prandial insulin response during an oral glucose tolerance test	Insulin Area Under the Curve (AUC)	Assessed during the intervention
Post-prandial glucose response during an oral glucose tolerance test	Glucose Area Under the Curve (AUC)	Assessed during the intervention
Matsuda index	Insulin Sensitivity measured with Matsuda index	Assessed during the intervention
Stumvoll metabolic clearance rate (MCR)	Insulin Sensitivity expressed as Stumvoll metabolic clearance rate	Assessed during the intervention

Collaborators and Investigators

• Sponsor: University of Illinois at Urbana-Champaign
• Investigators: Principal Investigator: Dominika M Pindus, PhD, University of Illinois at Urbana-Champaign

Study record dates

Study Major Dates

• Study Start (Actual): May 3, 2021
• Primary Completion (Estimated): May 31, 2024
• Study Completion (Estimated): May 31, 2024

Study Registration Dates

• First Submitted: May 24, 2021
• First Submitted That Met QC Criteria: June 6, 2021
• First Posted (Actual): June 15, 2021

Study Record Updates

• Last Update Posted (Actual): February 7, 2024
• Last Update Submitted That Met QC Criteria: February 5, 2024
• Last Verified: February 1, 2024

More Information

Terms related to this study

• Keywords: Insulin; Sedentary Behavior; Executive Function; Glucose; Event Related Potentials
• Additional Relevant MeSH Terms: Overnutrition; Nutrition Disorders; Overweight; Body Weight; Obesity
• Other Study ID Numbers: 20633

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No